Phenols or naphthols have been hitherto widely used as cyan couplers used in silver halide photographic light-sensitive materials. These are described, for example, in U.S. Pat. No. 2,369,929 and No. 2,474,293.
Cyan dye images obtained from the phenols or naphthols, however, have involved great problems in color reproduction. Namely, these cyan color-forming dyes have a poor sharpness at the shortwave side of the absorption spectrum, and also have unwanted absorption at the green portion, as well as at the blue portion in part. In the instances of color photographic papers or color reversal light-sensitive materials, there is no appropriate means for compensating them, making, in the recent circumstances, considerably poor the color reproducibility.
The present invention have now proposed novel cyan couplers, as disclosed in European Patent Application No. 249,453 and Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) No. 226653/1988. In these couplers, the cyan dyes formed have superior spectral absorption characteristics as compared with conventional phenol and naphthol type cyan couplers, bringing about a great improvement in the color reproducibility. They also have a high molar absorptivity of the color-forming dyes, and have made it possible to greatly decrease silver weight as compared with conventional couplers. However, the resulting dye images may have an insufficient fastness, and accordingly it has been sought to newly provide a cyan coupler capable of forming a dye image having a much higher fastness.